Vascular Dysfunction in Obstructive Sleep Apnea and Type 2 Diabetes Mellitus

Abstract

Despite the high prevalence of obstructive sleep apnea (OSA) in type 2 diabetes mellitus (DM), the attributable vascular risk from each condition is unknown. We hypothesize that OSA may have a similar effect on vascular function as type 2 diabetes does. Healthy normal-weight subjects, healthy obese subjects, subjects with type 2 diabetes, and obese subjects with OSA were enrolled. Vascular function was assessed with brachial artery ultrasound for flow-mediated dilatation (FMD) and in skin microcirculation by laser Doppler flowmetry. One hundred fifty-three subjects were studied: healthy normal-weight controls (NCs) (n = 14), healthy obese controls (OCs) (n = 33), subjects with DM (n = 68), and obese subjects with OSA (n = 38). The DM group did not undergo sleep study and thus may have had subclinical OSA. The OSA and type 2 diabetes groups had impaired FMD as compared to both the normal-weight and OC groups (5.8 ± 3.8%, 5.4 ± 1.6% vs. 9.1 ± 2.5%, 8.3 ± 5.1%, respectively, P < 0.001, post hoc Fischer test). When referenced to the NC group, a multiple linear regression model adjusting for covariates found that baseline brachial artery diameter (β = −3.75, P < 0.001), OSA (β = −2.45, P = 0.02) and type 2 diabetes status (β = −2.31, P = 0.02), negatively predicted % FMD. OSA status did not seem to affect nitroglycerin-induced vasodilation (endothelium-independent) of the brachial artery or vascular function in the skin microcirculation. OSA impairs endothelial function in the brachial artery to a similar degree as type 2 diabetes does. OSA, however, does not appear to affect brachial endothelium-independent vasodilation or skin microcirculatory function. Treatment of OSA in patients with concomitant type 2 diabetes, therefore, may be a potential therapeutic option to improve macro-, but not microvascular outcomes.

Myocardial Perfusion by Myocardial Contrast Echocardiography and Endothelial Dysfunction in Obstructive Sleep Apnea

“…[11][12][13][14][15][16][17][18][19] However, despite well-recognized endothelial abnormalities of large peripheral arteries in OSA patients, scarce data are available on the complex nature of vascular/endothelial function in otherwise healthy patients with moderate-tosevere OSA. In this study, we show for the first time that, in OSA, ED assessed at the macrocirculatory and microcirculatory beds parallels with the impairment of cardiac endothelial function/perfusion.…”

“…18 In this technique, the current was delivered through 2 drug delivery chambers (model LI 611, Perimed, Jarfalla, Sweden), which were placed on the ventral aspect of the right upper forearm 5 cm apart and were connected to a current intensity-regulated generator (Perilont, Perimed AB). Mean baseline perfusion, mean maximum perfusion, and maximum percentage of change in perfusion were calculated using modern Perimed software.…”

“…[11][12][13][14][15][16][17] Although they generally show abnormalities in the different aspects of endothelial function in OSA, the results show substantial variability, often with controversial findings. [11][12][13][14][15][16][17][18][19][20] This may be because of the concomitant confounding factors known to influence endothelial function independent of OSA. Also, myocardial blood flow reserve (MBFR) is a well-validated surrogate marker of coronary perfusion and provides an estimation of coronary flow reserve.…”

Obstructive sleep apnoea syndrome, endothelial function and markers of endothelialization. Changes after cpap

“…The level of circulating MPs in peripheral blood has been reported to be increased in several ischemic diseases [7]. It seems that MPs from activated leukocytes (CD62L_ MPs) are higher in patients with OSA and a positive correlation between circulating levels of CD62L_ MPs and nocturnal hypoxemia severity has been reported [16,17,18]. Nevertheless, other authors studying children with sleep breathing disorders observed that leukocyte CD11b+ MPs and platelet CD41a+ MPs were the microparticles that correlated the best with the apnoea-hypopnea index [19].…”

Weight Reduction Programs in Obese Sleep Apnea Patients: The Role of the Mediterranean Diet

“…OSAS is associated with significant systemic consequences, including cardiovascular morbidity and mortality, and the risk increases with the severity of the syndrome [3]. The pathophysiology underlying the link between OSAS and the cardiovascular system is attributed largely to systemic inflammation and oxidative stress, which are both contributors to endothelial dysfunction [4]. The treatment modalities of OSAS include Continuous Positive Airway Pressure (CPAP), weight loss, upper airway surgery, and oral devices [5].…”